I think both groups do good and we should have people that are confrontational and debate in a manner that holds their opponents accountable for using fallacy and cheats to defend their case (ala dawkins/harris/hitchens). Folks like that, that didn't back down, played a huge role in planting doubts in me early on because while I still held on to the JW lies for some time, I knew that many of the terrible things they said about god really had no defense that was intellectually honest. Some people are ready to be held accountable for their lack of logic. At the same time, others will be much more likely to be won over by different approaches like establishing atheist groups that demonstrate that atheists are no less moral or purpose in life than theists.
I say let everyone fight against the insanity of religion in their own way and they'll reach different groups of people. One group may turn off a few people to atheism, but they'll reach others that would otherwise been content to stay put were atheists only seeking to "form alliances" with them. One group may turn people off, and the other will reassure them. One group may fail to reach some due to their pulling punches, the other group will find them. There's a time and a place for both points of view and both strategies.